When packaging articles, it has been the practice to use containers formed from separate top and bottom trays which are adapted to nest relative to each other. The bottom trays are usually smaller than the top trays so that when the article to be packaged is placed in the bottom tray, the top tray is inverted and is telescoped over the side and end walls of the bottom tray to complete the container.
Since the size of the two trays is different, it has been necessary for users to purchase and store both top and bottom trays. In addition, since existing top and bottom trays all have end walls and side walls substantially the same height, it is necessary to use greater amounts of material to make the trays. Furthermore, since both top and bottom trays must be purchased and stored, if one of the trays is destroyed or lost, the other tray may become superfluous and may eventually be discarded, thus wasting material.